Safety chuck-clutch.



L.- B. COTTERMAN & J. L. ALGER.

SAFETY CHUCK CLUTCH.

APPLICATION FILED MAR. 29. 1am

" Patented Nov. 13, 1917;

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LEGBAND B. COTTEBMAN AND JESSE L. ALGER, OF" INDIANAPOLIS, INDIANA.

CHUCK-CLUTCH.

Specification of Letters Patent.

Patented Nov. 13, 1917.

Application filed March 29, 1917. Serial No. 158,836.

To all whom it may concern:

Be it known th TERMAN and JEssE' ALGER, citizens of the United States, residing at Indianapolis, in the county of Marion and State of Indiana, have invented certain new and useful Improvements in Safety Chuck-Clutches, of which the following is a specification.

Our invention relates to means for connecting a chuck, carrying a bit or other tool, with the spindle of a drill press, in a manner to automatically arrest the rotation of the bit when it is subjected to excessive strains, for preventing injur to the bit.

An important object of the invention is to provide means of the above mentioned character, which is adjustable for regulating its action, whereby the same may be emvention will be apparent during the course of the following description In the accompanying drawings forming a part of this specification and in which like numerals are employed to designate like parts throughout the same,

Figure l is a side elevation of a device -embodying my invention,

Fig. 2 is a similar view, parts being shown in central vertical section,

Fig. 3 is a plan view of the same, and,

Fig. 4: is a plan view of the lower head or member.

In the drawings, wherein for the purpose of illustration is shown a preferred embodiment of my invention, the device is shown as comprising an upper head or member 10, which is preferably cylindrical, and a lower head or member 11, which is also prefcylindrical. The upper head is propassing through openings 15 in the upper head 10, as shown. It is thus apparent that the heads 10 and 11 are pivotally connected so that they will not separate and that they are adapted to be rotated with respect to each other. The upper head '10 is provided we, LEGRAND B. 0012- with an upstanding shank 15', to fit within thesocket of the rotating head (not shown) of the drill press. Depending from the lower he or member 11 is a tapered member or sh nk 16, for connection with a chuck t;(n(it shown) which carries the bit or other Means are provided to normally lock the heads 10 and 11 together, so that they rotate together, comprising elements or balls 19, adapted to enter spherically curved recesses 20, in the head 11, and to operate within vertical cylindrical openings 21, in the head 10. The balls 19 are moved downwardly by suitably stifi' compressible coil springs 22, the tension of which ma be regulated by the top of the head 10, thus indicating the degree of compression of the springs 22.

In operation, the screws 23 are turned to obtain a desired degree of compression upon the springs 22, depending upon thesize of the bitwhich is employed. In normal operation, the springs 22 are sufliciently stifl to retain the balls 19 in the recesses 20, thereby locking heads 10 and 11 for rotation together, However, when the bit stops or becomes jammed, the upper head 10 may rotate with respect to the lower head 11, thus preventing the bit being broken.

It is to be understood that the form of our invention herewith shown and described is to be taken as a preferred example of the same, and that various changes in the shape, size, and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

Having thus described our invention, we claim:

1. In a device of the character described, the combination with an upper head provided with openings and scales arranged in proximity to the-openings, of an element seadjusting screws or mem ers 23, operating cured to the head to rotate it, a lower'head ings and to enter the recesses, springs ar-' ranged within the openings to move the locking elements into the recesses, adjusting' screws operatin within the openings to regulate the tenslon of the springs and having pointers traveling in proximity to for rotation together, a device secured to the scales, and an attaching member secured the upper head to rotate it, and an attaching to the lower head. member carried by 'the lower head.

2. In' a device of the character described, In testimony whereof we aflix our signa- 1.5 5 thg gombilnation wifth andupper 1head rotures in presence of twowitnesses.

vi e wit a recess orm'e in its ower ace, 7 a lower head carrying an upstanding stud ?%g f EGgg projecting into the recess and having an annular groove, a pin passing through the Witnesses: v 10 upper head and entering the annular groove, W. D. GIBSON,

yie ding means to normally lock the heads H. E. HARRIS. 

